Some 1991-1993 De Villes, Fleetwoods, Eldorados, and Sevilles equipped with a Hydra-matic 4T60-E (RPO M13) transaxle built on or before June 23, 1993 (Julian Date 174) may exhibit a transaxle bearing whine that is audible in first, second, and third gear. the whine is most audible on the "driver's" side of the vehicle while in second gear during a light throttle acceleration.
This condition may be caused if the bearing assembly fourth channel plate hub/channel plate (503/431), was improperly installed causing the needle bearings to leave indentation marks on the bearing race.
To correct this condition replace the bearing assembly, fourth channel plate hub/channel plate (503/431), located on the channel plate assembly (404/401). Refer to Figure 1.
P/N Description --- ----------- 8656393 Bearing Assembly, Fourth Channel Plate Hub/Channel Plate
Parts are currently available from GMSPO.
For warranty purposes use Labor Operation K7461 from the appropriate Labor Time Guide.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.